Impact of H2 Reduction on the Performance and Stability of Phenol Catalytic Wet Air Oxidation (CWAO) Over Cu−Ce/AC Catalysts

Graphical H 2 reduction reduces part of Cu 2+ to Cu + and Ce 4+ to Ce 3+ on the catalyst surface, and Cu and Ce can be stably anchored on the surface of the Cu−Ce/AC catalyst, which effectively improves the dispersion of the Cu component, and then slows down the loss of metal Cu. In this study, we utilized the carbon precursor derived from walnut shells to synthesize a series of Ce-modified Cu-based carbon catalysts (Cu−Ce/AC) via the impregnation method. We investigated the performance and stability of Cu−Ce/AC catalysts for CWAO phenol after H 2 reduction at various temperatures. The Cu−Ce/AC-250 catalyst exhibited its highest performance at 250 °C, achieving complete phenol conversion. Characterization results from techniques including XRD, BET, FTIR, ICP-OES, SEM-EDS, XPS, and H 2 -TPR indicated that the active components of the H 2 -reduced catalysts were more evenly distributed across the catalyst surface, thereby enhancing the availability of reactive sites for phenol oxidation. Simultaneously, under the appropriate temperature, the H 2 atmosphere can reduce a portion of the Cu 2+ on the catalyst surface to Cu + , thereby mitigating the loss of Cu components.